Coolant regulator

Ice from the ice plant arrives here 64 blocks at a time, and is spat out into the reactor at a rate of 16 blocks per second. The reactor only actually needs 5 blocks per second, so the remainder is recycled back to the ice chest. Waste not, want not...

Timers and trip alarms. If the ice supply stops - that is, if no ice is pumped out for two seconds - an alarm is tripped and the reactor stops.
If there is no "waste" ice being returned from the reactor, that indicates the reactor is using ice faster than it can be supplied. This is also a reason to trip.

Substation and switchyard.

The reactor puts out EHV power packets of about 1200EU to 1500 EU/packet. This needs to be stepped down for distribution on glass fibre cables, which can only carry 512 EU/packet max.
The transformers (up back) step 2048 EU/t down to 512 EU/t for storage in three banks of ten MFSUs, for a total capacity of 300 million EU.

Ice factory

A bank of sixteen IC2 Advanced Machines Singularity Compressors.
Produces 20 ice / sec at peak, though the reactor doesn't use anywhere near that much. Power consumption is about 200 EU/t at full load, or 20 EU/t at idle (i.e. just keeping the Singularity Compressors warmed up.)
The "advanced insertion pipes" from the Additional Pipes mod are used to supply the compressors with snowballs. Waste snowballs are (ironically) spat out into a lava disposal chute.

The ice factory has its own HV-> MV substation, complete with MSFU energy storage, to supply the compressors.
If the MFSU storage units empty completely, the compressors will stop (which means no more ice.) The MFSUs are monitored and a trip signal is sent if they empty completely.

In the reactor chamber. There are three, redundant, wireless redstone receivers in here, all of which are connected to the reactor.
Blue means "cooling down" or "safe". Green means "reactor running", or "you REALLY shouldn't be in here."

The fault trips board. Subsystems are monitored for correct operation. If any of the subsystems fail, the trip flag (red light) will latch up and shut down the reactor.
The buttons reset the trip flags. If the fault condition is still faulty, the trip flag won't reset. (You need to go find the fault and fix it.)

Master safety board. All three lights (emergency stop, manual isolate, and no-faults) must be green.
Once all three lights are green, you can go stand on the final safety feature - a pressure plate that activates the reactor.

View into the reactor from the operator's position - on top of the "Run" pressure plate. You have to stand on the pressure plate to make the reactor go. If you die, or if you step off the plate, the reactor shuts down.
Blue light means "cooling down". Green light means "reactor on." Notice the emergency stop buttons, i.e. the "HOLY SHIT!" buttons.

Control room wiring

The mechanism behind one of the trip latches. It's an RS flip-flop built from two NOR gates. (The built-in redpower2 RS latch has retarded behaviour, so I built my own.)
The R line is connected to the green light and reset pushbutton on the other side. The wireless trip reciever and red light are connected to the S line.
On some of the other trip latches, you need a repeater gate on the wireless reciever to make sure the pulses are at least 2 ticks long. 1-tick pulses tend to make the RS latch oscillate like crazy.

Reactor run logic. Three independent safety features must be activated (emergency stop reset, manual isolate lever, and dead-man's pressure plate.)
Additionally, the pink line will be high if ANY fault has occurred. Fault conditions inhibit reactor startup.

Containment vessel test

I tested the containment vessel by blowing it up.
The weak point in the containment vessel is where the pipes and cables exit the reactor chamber. The explosion blows through in that direction and makes a neat little hole.

Hole from the outside. The wall was only one block thick there anyway.
I could have reinforced it, but I chose to leave this weak point because reinforced stone is EXPENSIVE, and there's nothing valuable in the blast zone of this hole anyway.

Cooling regulator detail. Notice the unusual arrangement for the excess ice - it gets thrown out of a redpower2 tube system into a BC obsidian pipe.
An advanced insertion pipe will put the ice back into the chest if it can, otherwise it's sent to an incinerator.
I tried a few other redpower2-tube only configurations and I couldn't find a way to make it work without backing up the entire tube system. (Recall that, as a safety feature, I trip the reactor if there's any interruption in the flow of ice.)

New Stuff

I've prettied up the world some.
Poles were added to support the ice pipeline (so it doesn't look like it's hanging in midair.) Roofs were added to all the buildings.
New switchroom for switching customer's electricity supplies on and off at will :D